CDMA2000 (also known as C2K or IMT Multi‑Carrier (IMT‑MC)) is a family of 3G[1] mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a backwards-compatible successor to second-generation cdmaOne (IS-95) set of standards and used especially in North America and South Korea.

CDMA2000 compares to UMTS, a competing set of 3G standards, which is developed by 3GPP and used in Europe, Japan, and China.

The name CDMA2000 denotes a family of standards that represent the successive, evolutionary stages of the underlying technology. These are:

All are approved radio interfaces for the ITU's IMT-2000. In the United States, CDMA2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA).[2]


CDMA2000 1X (IS-2000), also known as 1x and 1xRTT, is the core CDMA2000 wireless air interface standard. The designation "1x", meaning 1 times radio transmission technology, indicates the same radio frequency (RF) bandwidth as IS-95: a duplex pair of 1.25 MHz radio channels. 1xRTT almost doubles the capacity of IS-95 by adding 64 more traffic channels to the forward link, orthogonal to (in quadrature with) the original set of 64. The 1X standard supports packet data speeds of up to 153 kbit/s with real world data transmission averaging 80–100 kbit/s in most commercial applications.[3] IMT-2000 also made changes to the data link layer for greater use of data services, including medium and link access control protocols and QoS. The IS-95 data link layer only provided "best efforts delivery" for data and circuit switched channel for voice (i.e., a voice frame once every 20 ms).


1XEV Mobile Phone Screenshot blackberry
BlackBerry smartphone displaying '1XEV' as the service status in the upper right corner.

CDMA2000 1xEV-DO (Evolution-Data Optimized), often abbreviated as EV-DO or EV, is a telecommunications standard for the wireless transmission of data through radio signals, typically for broadband Internet access. It uses multiplexing techniques including code division multiple access (CDMA) as well as time-division access to maximize both individual user's throughput and the overall system throughput. It is standardized (IS-856) by 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards and has been adopted by many mobile phone service providers around the world – particularly those previously employing CDMA networks.

1X Advanced

1X Advanced(Rev.E)[4][5] is the evolution of CDMA2000 1X. It provides up to four times the capacity and 70% more coverage compared to 1X.[6]


The CDMA Development Group states that, as of April 2014, there are 314 operators in 118 countries offering CDMA2000 1X and/or 1xEV-DO service.[7]


The intended 4G successor to CDMA2000 was UMB (Ultra Mobile Broadband); however, in November 2008, Qualcomm announced it was ending development of the technology, favoring LTE instead.[8]


  1. ^ "What really is a Third Generation (3G) Mobile Technology" (PDF). International Telecommunications Union. Archived from the original (PDF) on June 7, 2011. Retrieved October 28, 2012.
  2. ^ CDMA2000 trademark application,, November 17, 2009
  3. ^ "CDG : Technology : CDMA2000 1X". CDMA Development Group. Retrieved July 28, 2017.
  4. ^ "Evolution of CDMA Roadmap—Voice Perspective" (PDF). Alcatel-Lucent. May 13, 2010.
  5. ^ "Guidelines for using cdma2000 1x Revision E Features on Earlier Revisions" (PDF). 3GPP2. July 2011. Archived from the original (PDF) on July 5, 2016. Retrieved May 17, 2016.
  6. ^ "1X Advanced". Qualcomm. Retrieved September 18, 2013.
  7. ^ "CDG : CDMA Statistics". CDMA Development Group. Retrieved June 13, 2015.
  8. ^ Qualcomm halts UMB project, Reuters, November 13, 2008

External links


2G (or 2-G) is short for second-generation cellular technology. Second-generation 2G cellular networks were commercially launched on the GSM standard in Finland by Radiolinja (now part of Elisa Oyj) in 1991. Three primary benefits of 2G networks over their predecessors were that phone conversations were digitally encrypted; 2G systems were significantly more efficient on the spectrum enabling far greater wireless penetration levels; and 2G introduced data services for mobile, starting with SMS text messages. 2G technologies enabled the various networks to provide the services such as text messages, picture messages, and MMS (multimedia messages). All text messages sent over 2G are digitally encrypted, allowing the transfer of data in such a way that only the intended receiver can receive and read it.

After 2G was launched, the previous mobile wireless network systems were retroactively dubbed 1G. While radio signals on 1G networks are analog, radio signals on 2G networks are digital. Both systems use digital signaling to connect the radio towers (which listen to the devices) to the rest of the mobile system.

With General Packet Radio Service (GPRS), 2G offers a theoretical maximum transfer speed of 50 kbit/s (40 kbit/s in practice). With EDGE (Enhanced Data Rates for GSM Evolution), there is a theoretical maximum transfer speed of 1 Mbit/s (500 kbit/s in practice).The most common 2G technology was the time division multiple access (TDMA)-based GSM, originally from Europe but used in most of the world outside North America. Over 60 GSM operators were also using CDMA2000 in the 450 MHz frequency band (CDMA450) by 2010.


3G, short for third generation, is the third generation of wireless mobile telecommunications technology. It is the upgrade for 2G and 2.5G GPRS networks, for faster internet speed. This is based on a set of standards used for mobile devices and mobile telecommunications use services and networks that comply with the International Mobile Telecommunications-2000 (IMT-2000) specifications by the International Telecommunication Union. 3G finds application in wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV.

3G telecommunication networks support services that provide an information transfer rate of at least 0.2 Mbit/s. Later 3G releases, often denoted 3.5G and 3.75G, also provide mobile broadband access of several Mbit/s to smartphones and mobile modems in laptop computers. This ensures it can be applied to wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV technologies.

A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1979 and the early to mid-1980s. Each generation is characterized by new frequency bands, higher data rates and non–backward-compatible transmission technology. The first 3G networks were introduced in 1998 and 4G networks in 2008.


The 3rd Generation Partnership Project (3GPP) is a collaboration between groups of telecommunications standards associations, known as the Organizational Partners. The initial scope of 3GPP was to make a globally applicable third-generation (3G) mobile phone system specification based on evolved Global System for Mobile Communications (GSM) specifications within the scope of the International Mobile Telecommunications-2000 project of the International Telecommunication Union (ITU). The scope was later enlarged to include the development and maintenance of:

GSM and related 2G and 2.5G standards, including GPRS and EDGE

UMTS and related 3G standards, including HSPA

LTE and related 4G standards, including LTE Advanced and LTE Advanced Pro

Next generation and related 5G standards

An evolved IP Multimedia Subsystem (IMS) developed in an access independent manner3GPP standardization encompasses Radio Access Network, Services and Systems Aspects, and Core Network and Terminals. The project was established in December 1998 and should not be confused with 3rd Generation Partnership Project 2 (3GPP2), which specifies standards for another 3G technology based on IS-95 (CDMA), commonly known as CDMA2000.

The 3GPP support team (also known as the "Mobile Competence Centre") is located at the European Telecommunications Standards Institute (ETSI) headquarters in the Sophia Antipolis technology park in France.

3rd Generation Partnership Project 2

The 3rd Generation Partnership Project 2 (3GPP2) is a collaboration between telecommunications associations to make a globally applicable third generation (3G) mobile phone system specification within the scope of the ITU's IMT-2000 project. In practice, 3GPP2 is the standardization group for CDMA2000, the set of 3G standards based on the earlier cdmaOne 2G CDMA technology.

The participating associations are ARIB/TTC (Japan), China Communications Standards Association, Telecommunications Industry Association (North America) and Telecommunications Technology Association (South Korea).

The agreement was established in December 1998.

Ultra Mobile Broadband (UMB) was a 3GPP2 project to develop a fourth-generation successor to CDMA2000. In November 2008, Qualcomm, UMB's lead sponsor, announced it was ending development of the technology, favoring LTE instead.3GPP2 should not be confused with 3GPP; 3GPP is the standard body behind the Universal Mobile Telecommunications System (UMTS) that is the 3G upgrade to GSM networks, while 3GPP2 is the standard body behind the competing 3G standard CDMA2000 that is the 3G upgrade to cdmaOne networks used mostly in the United States (and to some extent also in Japan, China, Canada, South Korea and India).

GSM/GPRS/EDGE/W-CDMA is the most widespread wireless standard in the world. A few countries (such as China, the United States, Canada, Trinidad and Tobago, India, South Korea and Japan) use both sets of standards, but most countries use only the GSM family.

Cellular frequencies

Cellular frequencies are the sets of frequency ranges within the ultra high frequency band that have been assigned for cellular-compatible mobile devices, such as mobile phones, to connect to cellular networks. Most mobile networks worldwide use portions of the radio frequency spectrum, allocated to the mobile service, for the transmission and reception of their signals. The particular bands may also be shared with other radiocommunication services, e.g. broadcasting service, and fixed service operation.

Digital AMPS

IS-54 and IS-136 are second-generation (2G) mobile phone systems, known as Digital AMPS (D-AMPS), and a further development of the North American 1G mobile system Advanced Mobile Phone System (AMPS). It was once prevalent throughout the Americas, particularly in the United States and Canada since the first commercial network was deployed in 1993. D-AMPS is considered end-of-life, and existing networks have mostly been replaced by GSM/GPRS or CDMA2000 technologies.

This system is most often referred to as TDMA. That name is based on the abbreviation for time division multiple access, a common multiple access technique which is used in most 2G standards, including GSM, as well as in IS-54 and IS-136. However, D-AMPS has been competing against GSM and systems based on code division multiple access (CDMA) for adoption by the network carriers, although it is now being phased out in favor of GSM/GPRS and CDMA2000 technology.

D-AMPS uses existing AMPS channels and allows for smooth transition between digital and analog systems in the same area. Capacity was increased over the preceding analog design by dividing each 30 kHz channel pair into three time slots (hence time division) and digitally compressing the voice data, yielding three times the call capacity in a single cell. A digital system also made calls more secure in the beginning, as analogue scanners could not access digital signals. Calls were encrypted, using CMEA, which was later found to be weak.IS-136 added a number of features to the original IS-54 specification, including text messaging, circuit switched data (CSD), and an improved compression protocol. SMS and CSD were both available as part of the GSM protocol, and IS-136 implemented them in a nearly identical fashion.

Former large IS-136 networks, including AT&T in the United States, and Rogers Wireless in Canada, have upgraded their existing IS-136 networks to GSM/GPRS. Rogers Wireless removed all 1900 MHz IS-136 in 2003, and has done the same with its 800 MHz spectrum as the equipment failed. Rogers deactivated its IS-136 network (along with AMPS) on May 31, 2007. AT&T soon followed in February 2008, shutting down both TDMA and AMPS.

Alltel, who primarily uses CDMA2000 technology but acquired a TDMA network from Western Wireless, shut down its TDMA and AMPS networks in September 2008. US Cellular, which now also primarily uses CDMA2000 technology, shut down its TDMA network in February 2009.

IS-54 is the first mobile communication system which had provision for security, and the first to employ TDMA technology.

Enhanced Variable Rate Codec B

Enhanced Variable Rate Codec B (EVRC-B) is a speech codec used by CDMA networks. EVRC-B is an enhancement to EVRC and compresses each 20 milliseconds of 8000 Hz, 16-bit sampled speech

input into output frames of one of the four different sizes:

Rate 1 - 171 bits,

Rate 1/2 - 80 bits,

Rate 1/4 - 40 bits,

Rate 1/8 - 16 bits.

In addition, there are two zero bit codec frame types: null frames and erasure frames, similar to EVRC. One significant enhancement in EVRC-B is the use of 1/4 rate frames that were not used in EVRC. This provides lower average data rates (ADRs) compared to EVRC, for a given voice quality.

The new 4GV Codecs used in CDMA2000 are based on EVRC-B. 4GV is designed to allow service providers to dynamically prioritize voice capacity on their network as required.

The Enhanced Variable Rate Coder (EVRC) is a speech codec used for cellular telephony in cdma2000 systems. EVRC provides excellent speech quality using variable rate coding with 3 possible rates, 8.55, 4.0 and 0.8 kbit/s. However, the Quality of Service (QoS) in cdma2000 systems can significantly benefit from a codec which allows tradeoffs between voice quality and network capacity, which cannot be achieved efficiently with the EVRC.

An upgrade of the EVRC vocoder, known as EVRC-B, was recently introduced by 3GPP2. The EVRC-B speech codec is based on the 4GV concept and is the newest and most advanced speech codec for cellular applications. In addition to the Relaxed Code Excitation Linear Prediction (RCELP) used by EVRC, EVRC-B uses Prototype Pitch Period (PPP) approach for coding of stationary voice frames and Noise Excitation Linear Prediction (NELP) for efficient coding of unvoiced or noise frames. Using NELP and PPP coding at 2.0 kbit/s provides EVRC-B with superior flexibility in rate assignment, allowing it to operate at several operating points, each with a different trade-off between speech quality and system capacity. EVRC-B will replace EVRC as the main speech codec for cdma2000 and its first network commercial deployment is planned to start in 2007. A wideband extension, EVRC-WB, will provide speech quality that exceeds regular wireline telephony and its standardization process is planned to be completed at the summer of 2007.

EVRC-B can be also used in 3GPP2 container file format - 3G2.

Evolution-Data Optimized

Evolution-Data Optimized (EV-DO, EVDO, etc.) is a telecommunications standard for the wireless transmission of data through radio signals, typically for broadband Internet access. EV-DO is an evolution of the CDMA2000 (IS-2000) standard which supports high data rates and can be deployed alongside a wireless carrier's voice services. It uses advanced multiplexing techniques including code division multiple access (CDMA) as well as time division multiplexing (TDM) to maximize throughput. It is a part of the CDMA2000 family of standards and has been adopted by many mobile phone service providers around the world particularly those previously employing CDMA networks. It is also used on the Globalstar satellite phone network.EV-DO service has been or will be discontinued in much of Canada in 2015.An EV-DO channel has a bandwidth of 1.25 MHz, the same bandwidth size that IS-95A (IS-95) and IS-2000 (1xRTT) use, though the channel structure is very different. The back-end network is entirely packet-based, and is not constrained by restrictions typically present on a circuit switched network.

The EV-DO feature of CDMA2000 networks provides access to mobile devices with forward link air interface speeds of up to 2.4 Mbit/s with Rel. 0 and up to 3.1 Mbit/s with Rev. A. The reverse link rate for Rel. 0 can operate up to 153 kbit/s, while Rev. A can operate at up to 1.8 Mbit/s. It was designed to be operated end-to-end as an IP based network, and can support any application which can operate on such a network and bit rate constraints.

List of CDMA2000 networks

A list of CDMA2000 networks worldwide.

List of Nokia products

The following is a list of products branded by Nokia.

List of United States wireless communications service providers

This is a list of United States wireless communications service providers. The Cellular Telecommunications & Internet Association (CTIA), lists approximately 30 facilities-based wireless service providers in the United States as members. Competitive Carriers Association (CCA) has over 100 members. Besides the facilities-based providers there are 50+ virtual operators that use the top four networks to provide the service.


MediaTek Inc. (Chinese: 聯發科技股份有限公司; pinyin: Liánfā Kējì Gǔfèn Yǒuxiàn Gōngsī) is a Taiwanese fabless semiconductor company that provides chips for wireless communications, High-definition television, handheld mobile devices like smartphones and tablet computers, navigation systems, consumer multimedia products and Digital subscriber line services as well as optical disc drives.Headquartered in Hsinchu, Taiwan, the company has 25 offices worldwide and was the third largest fabless IC designer worldwide in 2016. Since its founding in 1997, MediaTek has been creating chipsets for the global market. MediaTek also provides its customers with reference designs.

Mobile broadband

Mobile broadband is the marketing term for wireless Internet access through a portable modem, USB wireless modem, or a tablet/smartphone or other mobile device. The first wireless Internet access became available in 1991 as part of the second generation (2G) of mobile phone technology. Higher speeds became available in 2001 and 2006 as part of the third (3G) and fourth (4G) generations. In 2011, 90% of the world's population lived in areas with 2G coverage, while 45% lived in areas with 2G and 3G coverage. Mobile broadband uses the spectrum of 225 MHz to 3700 MHz.

Mobile country code

The ITU-T Recommendation E.212 defines mobile country codes (MCC) as well as mobile network codes (MNC).


NetCologne is a regional telecommunications, cable television and Internet service provider in the Cologne region of Germany. It operates its own copper, coaxial, FTTB and CDMA2000 networks. It serves 518.000 customers and is owned by the city of Cologne. The company has around 900 employees.

Nokia 8210

The Nokia 8210 is a mobile phone by Nokia, announced on 8 October 1999 in Paris. At the time it was the smallest, lightest Nokia mobile phone on the market, thus its selling point was based on its design and customization, with removable Xpress-on covers. Six differently coloured Xpress-on covers are available, as well as many third party ones.

Personal Digital Cellular

Personal Digital Cellular (PDC) was a 2G mobile telecommunications standard used exclusively in Japan.After a peak of nearly 80 million subscribers to PDC, it had 46 million subscribers in December 2005, and was slowly phased out in favor of 3G technologies like W-CDMA and CDMA2000. At the end of March 2012, the count had dwindled down to almost 200,000 subscribers. NTT Docomo shut down their network, mova, on April 1, 2012 at midnight.


The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunications Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators.

UMTS specifies a complete network system, which includes the radio access network (UMTS Terrestrial Radio Access Network, or UTRAN), the core network (Mobile Application Part, or MAP) and the authentication of users via SIM (subscriber identity module) cards.

The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA) or 3GSM.

Unlike EDGE (IMT Single-Carrier, based on GSM) and CDMA2000 (IMT Multi-Carrier), UMTS requires new base stations and new frequency allocations.

Variable-Rate Multimode Wideband

Variable-Rate Multimode Wideband (VMR-WB) is a source-controlled variable-rate multimode codec designed for robust encoding/decoding of wideband/narrowband speech. The operation of VMR-WB is controlled by speech signal characteristics (i.e., source-controlled) and by traffic condition of the network (i.e., network-controlled mode switching). Depending on the traffic conditions and the desired quality of service (QoS), one of the 4 operational modes is used. All operating modes of the existing VMR-WB standard are fully compliant with cdma2000 rate-set II. VMR-WB modes 0, 1, and 2 are cdma2000 native modes with mode 0 providing the highest quality and mode 2 the lowest ADR. VMR-WB mode 3 is the AMR-WB interoperable mode operating at an ADR slightly higher than mode 0 and providing a quality equal or better than that of AMR-WB at 12.65 kbit/s when in an interoperable interconnection with AMR-WB at 12.65 kbit/s.

Now also a cdma2000 rate-set I compliant mode is implemented to the coder as mode 4. The average bitrate of the mode is 6.1 kbit/s (maximum is 8.55 kbit/s). Source coding bitrates are: Rate-Set I - 8.55, 4.0, 2.0, 0.8 kbit/s, Rate-Set II - 13.3, 6.2, 2.7, 1.0 kbit/s. VMR-WB uses 16 kHz sampling frequency. Algorithmic delay is 33.75ms.

VMR-WB can be also used in 3GPP2 container file format - 3G2.

VMR-WB was designed by Nokia and VoiceAge. It is based on AMR-WB.

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